1. Field of the Invention
The present invention relates to an integrated circuit having a first connection, a second connection, a substrate, and a control connection, wherein the control connection controls a conductivity of the integrated circuit between the first and the second connections.
2. Description of the Background Art
Such an integrated circuit can correspond to a transistor. In an implementation of an integrated circuit through an individual field-effect transistor, the first connection is defined by the source connection, the second connection by the drain connection and the control connection by the gate connection of the field-effect transistor. In an implementation as a bipolar transistor, the first connection is, for example, implemented by the emitter, the second connection by the collector and the control connection by the base of the bipolar transistor.
Depending on the application, such an integrated circuit, which has a first connection, a second connection, a substrate, and a control connection, must meet specific requirements for the dielectric strength between the first connection and the second connection, on the one hand, and between the first connection or the second connection and the substrate on the other hand. In this context, the dielectric strengths required within a circuit may be different. In one example application of a circuit to control a bridge circuit made of power transistors, such as is described in greater detail below, voltage differences between the first connection and the substrate result that can have variations on the order of magnitude of −10 to +60 V. In addition, there arise voltages of up to 20 V between the first connection and the second connection of such an integrated circuit, so that a voltage difference from the second connection of the integrated circuit to the substrate of 20 V+60 V=80 V can arise, for example. These requirements for the dielectric strength between the first connection and the second connection, on the one hand, and between the first connection or second connection and the substrate on the other hand, can in principle be met using specially designed individual transistors.
The design and manufacture of individual transistors individually adapted for special requirements in each case is very costly. The alternative of restricting the applications to those which can be implemented by using existing individual transistors as integrated circuits would, however, undesirably limit the number of possible applications.